JP2014160257A - Optical module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a support element and a method for supporting an optical element which allow in a simple manner a high accuracy and a high control bandwidth in positioning and orienting the optical element and extension of the lifetime of the support element.SOLUTION: An optical module comprises: a support unit; and at least one bipod 109.1 for holding and/or positioning an optical element 106.1 of a microlithographic projection exposure system relative to the support unit. The bipod 109.1 includes two bipod braces, for each of which a brace foot is directly or indirectly connected to the support unit 110 at a first end and a brace head is directly or indirectly connected to an optical element 106.1 at a second end, and which can be adjusted by at least one lever 113. At least one direction of motion of the lever is outside of the bipod plane, and a connection unit has at least one flexure with precisely one bending plane.

Description

The present invention relates to an optical module. The present invention can be used in connection with any optical device or optical imaging method. In particular, the present invention can be used in connection with microlithography used in the manufacture of microcircuits.

With respect to this application, application number 61/114, filed November 14, 2008,
Claims the benefit of US Patent No. 119 (e) (1) of 540 US provisional patent application.
It also claims the priority of the German patent application with application number 10 2008 049 746.0, filed on September 30, 208.

US Provisional Patent Application No. 61 / 114,540 and Application No. 10 2008
Each of the contents of the German patent application 049 746.0 is part of this application and is hereby incorporated by reference.

This application includes references cited by reference and references forming part of the present application. In the event of a discrepancy between the explicit disclosure of this application and the disclosure of a cited reference included by reference, the disclosure of this application shall prevail.

In addition to the use of components designed for maximum accuracy, especially in the field of microlithography, in operation, in order to obtain a correspondingly high imaging quality, the optical module of the imaging device, and thus for example Modules with optical elements such as lenses, mirrors, and gratings, as well as the position and orientation of the masks and substrates used should be set as accurately as possible within the specified settings, or such components may be specified (In the meaning of the present invention, the term optical module refers to an optical element alone and to a combination of such an optical element and further components such as holder parts, for example). Can mean both solids).

For this purpose, a support structure in which a plurality of support elements cooperate in a parallel kinematic fashion is often used to position and position the optical element in all six degrees of freedom. A typical example of such parallel kinematics is the so-called hexapod, in which six support elements (usually three pairs, so-called bipods) are used to connect the optical element to a larger support unit in the form of a ring cage. Determine positioning and posture. In many cases, as a support element, for example, Patent Document 1 (Shibazaki), the entire disclosure of which is included herein by reference.
As is known from, simple leaf spring elements are used here.

Since these configurations are relatively high in a direction perpendicular to the plane of the cage, manipulators can be used in optical system configurations where the optical elements are dense to ensure the desired distance between the optical elements. In general, it has the disadvantage of having to be nested within each other. This involves mounting two or more optical elements with their imaging error because the optical elements can only be mounted to rotate within a limited range relative to each other (eg, about the optical axis of the system). There is a further disadvantage that it is often impossible to combine such that they can be compensated for each other (eg caused by deformation of the optical system).

Patent Document 2 (Shibazaki), the entire disclosure of which is incorporated herein by reference, discloses a hexapod structure that is thin in the direction of the optical axis, in which the optical element is supported by six support members. Each support member is joined to an adjacent component by a flexure that acts in the form of a ball joint at both ends. Here, the adjustment of the optical element is performed by changing the joint point of the support member assigned to the external support structure so that the joint point of the support member assigned to the optical element is particularly displaced in the direction of the optical axis of the optical element. It is performed by displacing in the tangential direction with respect to the circumferential direction.

As a result of the joints used in the form of ball joints, the desired adjustment movement is achieved within a small area, while the two flexures have a relatively small cross-sectional area, especially under dynamic loads (high acceleration However, there is a problem that a relatively high stress is generated in the bending element even under a static load alone. As a result, firstly, the lifetime of the manipulator of the optical element is limited or relatively low accelerations are allowed (with respect to the specified adjustment range), so that only relatively small adjustment movements can be made. This is very disadvantageous in view of the tendency to move more with a larger adjustment range.

A further disadvantage of this configuration is that the tilting motion possible in the area of the ball joint can lead to falsification of the position of the joint point assigned to the optical element in the direction of the optical axis, which in turn can reduce the positioning accuracy. is there.

International Publication No. 02/16993 European Patent No. 1632799

The object of the invention is therefore not to have the above-mentioned drawbacks or at least to a limited extent, in particular the positioning of the optical element with a large adjustment movement (and thus high acceleration in the optical element). And attitude control with high accuracy and large control bandwidth (control bandwidt
It is to provide a support element and method for supporting an optical element, which makes it possible in a simple manner to obtain h) and extend the life of the support element.

The present invention provides a particularly high accuracy and a particularly large control bandwidth for positioning and attitude of optical elements with large adjustment movements when the flexures of the support elements are configured as bending elements that are elongated transverse to their bending axes. And the recognition that it is possible to extend the life of the support element. In this simple manner, the cross-sectional area of each flexure is increased so that a relatively moderate stress is generated even with a large dynamic load.

This arrangement allows assigning clearly distinguishable regions of the support element to regions where movement of various degrees of freedom is permitted or restricted, and more easily captures these regions.
There is also the advantage that the flexure can be configured so that it can. Thus, for example, the mobility of the support element in the region of the support member can be advantageously severely limited within some degrees of freedom, while other degrees of freedom of motion decoupl elsewhere in the support member.
ing) occurs. Thereby, the complexity of the control concept is reduced, and the accuracy of positioning and posture determination of the optical element can be increased.

Thus, according to a first aspect, the invention is a support element, in particular for an optical element for microlithography, comprising a support member, a first connection element connecting the support member to an external support unit, And a second connecting element for connecting the supporting member to the optical element. The support element is configured to cooperate in parallel motion with a further support element to position and position the optical element with respect to the external support unit in six degrees of freedom.

The support member includes a plurality of first flexures, the first connection element and / or the second connection element includes at least one second flexure, and the first flexure and the second flexure are respectively Define the bending axis. Limiting the movement of the optical element relative to the support unit can be achieved with a plurality of first and second flexures with a maximum of two degrees of freedom. Each of the first flexure and the second flexure is elongated along the bending axis.

According to a further aspect, the present invention is a support element, in particular for an optical element for microlithography, comprising a support member, a first connection element for connecting the support member to an external support unit, and an optical support member. A second connecting element connected to the element and configured to cooperate in parallel motion with a further support element to position and position the optical element relative to the external support unit with six degrees of freedom. Relates to the support element. The first connecting element is a second to the support member
A first connecting region relative to the first connecting element is configured to apply a displacement in the first direction to the support member in order to generate a displacement in the second direction of the second connecting region of the connecting element. . The support member includes a plurality of first flexures, and the first connection element and / or the second connection element has at least one second flexure. The first flexure is second with respect to the first connection region about the rotation axis in the operation plane defined by the first direction and the second direction.
The connection region is configured and arranged to prevent rotation of the connection region.

According to a further aspect, the present invention is an optical module, in particular for microlithography, comprising an optical element, a plurality of support elements and an external support unit, the plurality of support elements comprising:
The present invention relates to an optical module that positions and positions an optical element in parallel motion with respect to an external support unit with six degrees of freedom. At least one of the plurality of support elements is a support element according to the present invention.

According to a further aspect of the present invention, the present invention provides an optical module, which holds and / or holds an optical element of a microlithographic projection exposure system with respect to the support unit and the support unit.
Or at least one bipod for positioning, wherein the bipod includes two bipod braces, each of the bipot braces having a first end with a brace foot connected directly or indirectly to the support unit, and a second end In this optical module, the brace head is directly or indirectly connected to the optical element, and at least one of the brace head and the connection line connecting the two brace feet are located on the bipod plane. Here, the spacing between the brace feet along the connecting line can be arbitrarily greater than the spacing between the brace heads. Alternatively, the spacing between the brace feet along the connecting line may be less than or equal to the spacing between the brace heads. Furthermore, the spacing between the brace feet can be adjusted by at least one lever which is held on the bearing and engages at least one brace foot via the connection unit and is movable in at least one direction of movement. , At least one direction of movement of the lever is out of the bipod plane and the connecting unit has at least one flexure with exactly one bending plane, the flexure having a rigid configuration perpendicular to the bending plane. Has to have.

According to a further aspect, the invention is an optical imaging device, in particular for microlithography, comprising an illumination device, a mask device containing a mask comprising a projection pattern, a projection device having an optical element group, and a substrate. The present invention relates to an optical imaging device including a substrate device for housing. The illumination device is configured to illuminate the projection pattern, and the optical element group is configured to project the projection pattern onto the substrate. The illumination device and / or the projection device comprises an optical module according to the invention.

According to a further aspect, the present invention is a method for supporting an optical element, in particular for microlithography, wherein the optical element is supported on an external support unit via a plurality of support elements,
Positioned and positioned in parallel motion relative to the external support unit with a degree of freedom, the support element is connected to the external support unit via the first connection element and to the optical element via the second connection element The present invention relates to a method having a support member connected thereto. The support member includes a plurality of first flexures, the first connection element and / or the second connection element have at least one second flexure, and the first flexure and the second flexure are respectively Define the bending axis. Through a plurality of first flexures and second flexures, the movement limitation of the optical element relative to the support unit can be achieved with a maximum of two degrees of freedom, and bending is performed in each of the first flexure and the second flexure. A joint that is elongated along the axis is used.

According to a further aspect, the invention is finally a method for supporting an optical element, in particular for microlithography, the optical element being supported on an external support unit via a plurality of support elements, with 6 degrees of freedom. Positioned and oriented in parallel motion relative to the external support unit, the support element is connected to the external support unit via the first connection element and to the optical element via the second connection element. The present invention relates to a method having a support member. The first connecting element generates a displacement in the second direction of the second connecting region of the second connecting element relative to the support member;
A displacement in a first direction is applied to the support member at the first connection region of the first connection element. The support member is
The first connection element and / or the second connection element includes a plurality of first flexures, and has at least one second flexure. The second through the first flexure with respect to the first connection region centered on the rotation axis in the operation plane defined by the first direction and the second direction.
The connection area is prevented from rotating.

Further preferred designs of the invention will become apparent from the following description of preferred embodiments with reference to the appended claims or the accompanying drawings.

Preferred embodiment of an optical imaging device according to the invention, comprising an optical module according to the invention, comprising a support element according to the invention, which can carry out a preferred embodiment of the method according to the invention for supporting an optical element FIG. FIG. 2 is a schematic top view of a preferred embodiment of an optical module according to the invention of the imaging device of FIG. 1. 3 is a schematic cross-sectional view (along line III-III in FIG. 2) of the optical module of FIG. FIG. 4 is a schematic cross-sectional view (along line IV-IV in FIG. 2) of the optical module of FIG. FIG. 3 is a schematic perspective sectional view of a part of a preferred embodiment of a support element according to the invention used in the optical module of FIG. 2. FIG. 6 is a schematic top view of a further part of the support element of FIG. 5. FIG. 6 is a schematic top view of a further part of the support element of FIG. 5. 2 is a block diagram of a preferred embodiment of the method according to the invention for supporting an optical element that can be implemented in the optical imaging device of FIG. A to D are schematic cross-sectional views of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. FIG. 3 is a schematic perspective view of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. 2. FIG. 3 is a schematic perspective view of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. 2. FIG. 3 is a schematic perspective view of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. 2. FIG. 11B is a schematic perspective sectional view (along line XIB-XIB in FIG. 11A) of the support element of FIG. 11A. FIG. 3 is a schematic perspective view of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. 2. FIG. 3 is a schematic perspective view of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. 2. A to E are schematic cross-sectional views of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. A to D are schematic cross-sectional views of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. FIG. 3 is a schematic sectional view of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. 2. FIG. 3 is a schematic sectional view of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. 2. FIG. 3 is a schematic sectional view of a part of a further preferred embodiment of a support element according to the invention that can be used in the optical module of FIG. 2.

First Embodiment With reference to FIGS. 1 to 8 below, a preferred embodiment of an optical support element according to the invention used in an optical module according to the invention of an optical imaging device according to the invention for microlithography will be described. explain. At that time, in order to simplify the following description, an xyz coordinate system in which the z direction indicates the vertical direction is introduced. However, it will be appreciated that in other variants of the invention any other spatial alignment of the components of the imaging device can be performed.

FIG. 1 shows a microlithographic apparatus 101 operating with UV light having a wavelength of 193 nm.
1 shows a schematic view of a preferred embodiment of an optical imaging device according to the invention in the form of

In this example, the optical element of the optical element group is a refractive optical element in the form of a lens, a prism, a plate, or the like. However, it is obvious that in other variants of the invention, the refractive optical element, the reflective optical element and / or the diffractive optical element can be used alone or in any combination.

The microlithography apparatus 101 comprises an illumination system 102, a mask device 103, an optical projection system in the form of an objective lens 104, and a substrate device 105. The illumination system 102 comprises a mask 10 arranged on a mask table 103.2 of the mask device 103.
3.1 is illuminated with a projection light beam (not shown in more detail). There is a projection pattern on the mask 103.1, and the projection pattern is the optical element group 1 arranged in the objective lens 104.
The wafer table 105.2 of the substrate apparatus 105 with a projection light beam through the optical element 06.
It is projected onto a substrate in the form of a wafer 105.1 placed thereon.

In addition to the light source 102.1, the illumination system 102 comprises in particular a further optical element group 107, through which the projection light beam is formed and guided. Optical element groups 106 and 10 as described below by way of example using optical element 106.1 of optical element group 106.
Seven individual or all optical elements are held in an optical module 108 according to the invention.

As can be inferred from FIGS. 2 to 4 in particular, the optical module 108 comprises an optical element 106.1.
In addition, a holding device 109 for the optical element 106.1 or for the multi-component optical assembly 106 is provided, which is mechanically connected to the objective lens housing or possibly the objective lens. Forms part of the housing, thus the weight and the optical element 106.1
Alternatively, static loads and dynamic loads acting on the optical assembly 106 are supported by the floor or the foundation structure.

The holding device 109 comprises an external support unit in the form of an external ring 110, which is connected to an internal support unit in the form of an internal ring 112 via a plurality of support elements 111 according to the invention.

The outer ring 110, the support element 111, and the inner ring 112 are joined together in this example. For this purpose, they can be produced, for example, by wire erosion and, if necessary, further machining processes from solid blocks. However, it will be apparent that other holding devices made from a plurality of assembly components (using any suitable assembly method) can be used with other variations of the present invention.

The holding device 109 of this example includes six support elements 111, each of which is divided into a pair of bipods 109.1. Three bipods 10 formed in this way
9.1 is evenly distributed in the circumferential direction U around the periphery of the optical element 106.1, so that a support structure configured in parallel motion in the form of a hexapod is obtained, whereby the optical element 106. 1
Statically confirmed support is obtained. Here, the bipod 109.1 is an optical element 106.
1 includes an optical axis (z direction) and a radial direction R respectively defined by 1.
Are arranged symmetrically (in a neutral position) with respect to the radial plane defined by

The support element 111 allows the optical element 106.1 fixed to the inner ring 112 in any conventional manner (not described in more detail here) to be adjustable (actively in all six degrees of freedom in space). And / or passively) configured to be positionable and poseable. For this purpose, each support element 111 has a lever 113 connected to the outer ring 110.
A first connecting element in the form of The lever 113 is connected to one end of the support member 114 in the first connection region, and the other end of the support member 114 is connected to the second connection element 115 in the second connection region. The second connection region 115 is further connected to the inner ring 112.

In general, the optical module 108 of the executions according to the present description comprises a support unit 110, preferably an external support unit such as, for example, an external ring 110. The optical module 108 further comprises at least one bipod 109.1 for holding and / or positioning the optical element 106.1 of the microlithographic projection exposure system 101 relative to the support unit 110, wherein the bipod 109.1 is supported by It comprises two bipod braces, also referred to as members 114, each of which has a brace foot connected directly or indirectly to the support unit 110 at a first end and a brace head at the second end with an optical element 106.1. Connected directly or indirectly. The connection between the brace head and the brace foot is such that at least one brace head and the connection line connecting the two brace feet are located on the bipod plane, and the distance between the brace feet along the connection line is Greater than the spacing between the brace heads, the spacing between the brace feet being held on the bearing (113.1 in FIG. 6) and engaging at least one brace foot via the connecting unit At least one lever 11 movable in the direction
3 can be adjusted. Here, at least one movement direction of the lever is outside the bipod plane bipod plane. In addition, the joint unit has at least one flexure with exactly one bending plane (eg 114.1, 114.2 in FIG. 5), the flexure having a rigid configuration perpendicular to the bending plane. It is like that.

Alternatively, the spacing between the brace feet along the connecting line may be less than or equal to the spacing between the brace heads. Generally, the spacing and intersection between bipod braces defined by these,
Alternatively, the intersection of lines along the bipod brace may cause the platform or member to be tilted when multiple bipod elements (eg, in the form of hexapods) in parallel motion act on a spatially aligned platform (or member). Define the location of the tilt axis to bring.

In the general embodiment described with respect to the optical module 108, by way of example, the bipod's bipod brace may be connected directly to the outer ring (or support unit), but as described above, the bipod's second bipod brace is, for example, It is indirectly connected to the outer ring 110 via the lever 113. Alternatively, both bipod braces may be indirectly connected to the outer ring (with support unit 110), for example via each lever 113 (or generally via an actuator). Here, when changing the spacing between the brace feet and / or the position of the brace foot relative to the support unit 110, it is advantageous if the brad head of the bipod is movable in multiple directions depending on the position of the brace foot. This provides the possibility that the optical element can be directly or indirectly articulated to the brace head with multiple degrees of freedom. At this time, the number of degrees of freedom also varies depending on the further mounting element holding the optical element. Preferably, the optical module 108 comprises three bipods that form hexapods as described above. In this case, the optical module 108 comprises three bipods corresponding to at least one bipod, preferably each of the same configuration, which are hexapods for holding and / or positioning the optical element relative to the support unit. Each bipod forming a structure and corresponding to at least one bipod is assigned a corresponding lever and connection unit. The parallel kinematics formed by hexapods, which can position the optical element with up to 6 degrees of freedom and without being largely restrained, have the advantage that all actuators (lever) act directly on the same moving platform. Here, the platform is a unit or module connected to the bipod brace head. This can be, for example, the optical element itself (in the case of a direct connection of the brapod head of a bipod brace) or, for example, an internal retaining ring for an optical element that can also comprise a connecting element described in more detail below.

One advantage of parallel kinematics is that each actuator has a smaller mass than serial kinematics acting on its own adjustment platform with additional mass. With regard to the added mass, the reduction of the overall mass of the parallel kinematics advantageously provides a natural frequency spectrum in which the lowest natural frequency is usually significantly higher than the lowest natural frequency of the serial kinematics. This is because the latter becomes the square root of the reciprocal mass as the first approximation. By increasing the natural frequency, excitation of vibration of the optical module is prevented. This is very important in optical modules such as those used in microlithographic projection exposure systems, since otherwise high optical resolution cannot be obtained. Due to its low mass, parallel kinematics also has better dynamic characteristics than serial kinematics. A further advantage of parallel kinematics is that no moving wires are required and therefore there is no risk of receiving restraining forces from the cable. Furthermore, parallel kinematics can be made flatter and smaller than serial kinematics. This is particularly the case when optical elements with expensive free-form surfaces as refracting and / or reflecting surfaces are omitted, since the optical elements are often placed very close to each other at this time. It is also a decisive advantage in. A further very important aspect in the precision optics used in microlithographic projection exposure systems is that parallel kinematics, such as the hexapods mentioned above, do not introduce additional induction errors that occur with serial kinematics. . Therefore, in the parallel kinematics, the maximum positional accuracy with respect to the optical element of the optical module 108 can be obtained.

In the general embodiment described with respect to the optical module 108, as described above, one bipod brace head may be directly engaged with the optical element. Alternatively, the brace head may indirectly engage the optical element, and a connecting element 115, described in more detail below, may be provided between the brace head and the optical element, or the optical element may also be a retainer, eg, an internal It may be held in a retaining ring. Usually, but not necessarily, when the optical element is held in the optical module by a hexapod, the two brace heads of the bipod engage the optical element in the same manner.

In a general embodiment of the optical module 108, at least one direction of movement of the lever is positioned out of the bipod plane, so that the module 108 is flatter and thus more compact in a direction perpendicular to the connection line of the brace foot. Can be configured. As a result, the advantages of the small configuration of parallel kinematics such as the hexapod are further optimized.
If the lever movement direction is perpendicular to the bipod plane, the lever movement in the direction perpendicular to the connection line between the brace feet does not require any space, so that the smallest structure can be obtained.

In order for the spacing between the brace feet of the general embodiment of the optical module 108 to be variable or adjustable, at least one brace foot must be connected to the moving lever via the joint unit. Don't be. This is especially true because bipod braces usually have a rigid structure, i.e. their length does not change substantially, so the change in the spacing between the brace feet is the angle between the bipod brace that is moved by the lever and the lever itself. This will inevitably bring about changes. Here, the joint unit includes at least one first flexure. For example, solid state joints
In order to make full use of the parallel kinematics formed by the optical module 108 with respect to positional accuracy when a flexure such as is used, the flexure has exactly one bending plane. This prevents the flexure's parasitic bending in a direction away from the bending plane from displacing the brace foot engaged with the joint unit in an undesirable parasitic direction. This displacement reduces positional accuracy by causing the associated brace head of the bipod to perform undesirable parasitic motions. The flexure must have a rigid configuration in order to have exactly one bending plane in a direction outside the bending plane, for example in a direction perpendicular to the bending plane.

The relative term “rigid” means that the flexure has a first resistance moment in the direction of the bending plane and a second resistance moment in the direction perpendicular to the bending plane, where the second resistance moment is the first. Means at least twice the magnitude of the resistance moment. The resistance moment in the direction of the bending plane means a resistance moment that is greatly decisive in the direction of the bending plane when the flexure is under bending stress. Similarly, the second resistance moment means a resistance moment that greatly acts in a direction perpendicular to the bending plane when the flexure is under bending stress. In general, the greater the second resistance moment, the greater the stiffness of the flexure configuration in the direction perpendicular to the bending plane. This consideration applies generally in any direction and is not limited to a direction perpendicular to the bending plane. Depending on the required positional accuracy of the optical elements and the length of their bipod braces and their connections to the optical elements, which are well taken into account if there are additional flexure geometries, high stiffness requirements may arise. Therefore,
The second resistance moment may need to be at least 5 times greater than the first resistance moment or at least greater than 10 times.

Here, the resistance moment means a quotient of an axial sectional secondary moment (ie, area inertia moment) and a maximum distance from the outermost edge (extreme fiber) of the flexure to a neutral axis (neutral fiber). The resistance moment gives the maximum stress load as the quotient of the bending moment and the resistance moment at a given bending stress (at a given bending moment). In order to take into account the maximum tangential stress due to torsional strain, a so-called resistance moment or torsional resistance moment is substituted for the resistance moment.

In order to meet the above stiffness requirement in a direction deviating from the bending plane, for example, perpendicular to the bending plane, the flexure often has a bending axis extending perpendicular to the bending plane, where the bending axis It is sufficient that the length of the flexure in this direction is at least twice the maximum cross-sectional dimension of at least one flexure of the bending unit extending in the bending direction perpendicular to the bending axis. For example, this condition is not met if the flexure is formed as a leaf spring joint having a square cross section perpendicular to the bending plane. On the other hand, if the flexure is provided with a rectangular cross section perpendicular to the bending plane and the long side of the rectangular cross section is perpendicular to the bending plane, this condition is satisfied if the aspect ratio of the rectangular cross section is 2.

Each support member 114 (forming a bipod brace) in this example of FIGS.
Optical elements 106. at the location of the radial plane assigned to each bipod 109.1.
Extends generally parallel to the associated tangential direction T (defined by the tangent to 1). In this embodiment, each support member 114 has four first flexures 114.1-114.4 (FIG. 5) each defining a first bending axis. At this time, the bending axes of the flexures 114.1 and 114.3 or 114.2 and 114.4 extend in parallel with each other, but the two pairs 114.1, 114.3 and 114.2, 114 .4 bending axes extend transversely to each other (more precisely, here perpendicularly).

As shown and described in FIG. 5, the joint unit of the general embodiment of the optical module 108 has a further flexure 114. Having a further bending plane generally perpendicular to the bending plane of the at least one flexure 114.1. 2 may be provided. The further flexure 114.2 preferably has a further bending axis perpendicular to the further bending plane. Therefore, the bipod 109 connected to the lever 113 by the joint unit.
. One brace foot 114 is supported by a flexure that intersects the axis of rotation of each other so that the brace foot and thus the associated bipod brace are separated in two degrees of freedom. If the intersecting flexures are properly positioned, especially the spacing between intersecting rotation axes (
If the spacing of the crossed axes of rotation is within or even shorter than the flexure perpendicular to the bending axis, then an approximation to the ball joint is obtained.

In order to take full advantage of the parallel kinematics provided by the optical module 108 with respect to positional accuracy in the use of flexures, eg solid joints, the further flexure 114.2 perpendicular to the further bending plane may also have a rigid configuration. preferable.
At this time, the further flexure has a first resistance moment in the direction of the further bending plane and a second resistance moment in a direction perpendicular to the bending plane, the second resistance moment being the first resistance moment. At least twice the magnitude of the moment. At least 1 for stiffness
The description given above with respect to one flexure applies equally to the further joints.

In order to minimize the parasitic motion of the brace foot connected to the flexure when the bipod brace 114 is subjected to torsional stress that can cause flexure torsion, the bipod brace 114 can also be And more flexure 11
4.2 is configured such that the resistance pole moment about this torsion axis is at least twice the resistance moment in the direction of the further bending plane.

In a general embodiment of the optical module 108, this is a plane in which the bending plane of at least one flexure of the joint unit is parallel to the plane of symmetry of the optical element or perpendicular to the optical axis in the projection exposure system. Can be configured to be parallel. In this case, the flexure bending axis extends parallel to the optical axis. In the embodiment according to FIGS. 2 to 5 such a flexure corresponds to the joint 114.1. If this embodiment comprises an optical module comprising a joint unit with a further flexure, the further bending plane of the further flexure is preferably perpendicular to the plane of symmetry of the optical element, or the further bending plane is in the projection exposure system Parallel to the optical axis. Such a further flexure is the joint 114.2 in the embodiment according to FIGS. Here, especially when the optical module 108 forms a hexapod structure as described above, the further bending plane of the further flexure is parallel to the bipod plane.

FIG. 6 shows that the lever 113 associated with each of the support members 114 has a second flexure 113.
. 1 is connected to the outer ring 110 through 1. Second flexure 113.
1 defines the second bending axis (in the neutral position of the holding device 109) and thus the axis of rotation of the lever 113 extending parallel to the optical axis of the optical element 106.1.

In the optical module 108, the flexure 113.1 is in such a place,
When the bipod plane extends parallel to the optical axis, the operating direction of the lever is perpendicular to the bipod plane. In general, regardless of the optical axis, the direction of movement of the lever can be perpendicular to the bipod plane. At this time, the bending plane of the at least one flexure 114.1 is perpendicular to the bipod plane. The bending axis of at least one flexure 114.1 is
At this time, it is parallel to the bipod plane.

The lever 113 is an adjustment device 11 around the rotation axis defined by the flexure 113.1.
6 (described later in more detail). At this time, the first connection region 114.5 of the support member 114 is displaced in the related tangential direction T (x direction). This operation is performed by the first flexures 114.2 and 114. which are displaced in the direction of the optical axis of the optical element 1061.
4 and the abutment force of the further support element 111 assigned to the bipod 109.1, the second connection region 114.6 extending at least partially in the optical axis direction (z direction) of the optical element 106.1. Converted to motion.

In the optical module according to the embodiment described here, at least one flexure 114.1 or a further flexure 114.2 of the joint unit is configured as a leaf spring, as shown in FIG. Furthermore, the lever 11 assigned to each bipod 109.1.
The third bearing may be configured as a flexure 113.1 that joins the lever 113 to the support unit 110.

Here, each of the first flexures 114.1 to 114.4 and the second flexure 113.1 has an elongated configuration along its bending axis, in contrast to the first cited patent document 2 (Shibazaki). Configured as follows. This includes flexures 114.1 to 114.4 or 113.
. 1 is enlarged, each of the flexures 114.1 to 114.4, 113.
Flexures 114.1-114.4, 113.1 even under large loads during operation
There is an advantage that only moderate stress is generated.

Compared to the prior art configuration for active positioning / attitude determination of optical element 106.1,
This is the flexure of 114.1 to 114.4 or 113.1 (sometimes long term)
Higher acceleration is possible due to less stress at the joints 114.1-114.4 without incurring overload, thus allowing greater adjustment movement with a specified control bandwidth of displacement of the optical element 106.1. Provides the advantage of being able to.

A further advantage of this configuration is that the operation with individual degrees of freedom is assigned to a clearly distinguished flexure. Thereby, the assumption grasp of the adjustment operation in each support element becomes easy.

Finally, a configuration that is short in the transverse direction with respect to the bending axis of the second flexure 113.1, and thus as a pure rotary joint, is centered on an axis that intersects the bending axis of the second flexure 113.1. There is an advantage that only a slight inclination of the lever 113 can occur. This eliminates the tilt that causes the deviation from the desired position, so that this is the optical element 10.
The accuracy of the position and orientation of 6.1 and the stability of the position and orientation of the optical element 106.1 under dynamic load are greatly affected.

In order to reduce such inclination, the flexure 113.1 constituting the bearing of the lever 113 is used.
Can have exactly one bending plane, so that the flexure of the bearing has a rigid structure perpendicular to the bending plane. This embodiment is particularly preferred in the embodiments described herein for the optical module 108 due to the advantages described above. even here,
The term “rigid” means that the flexure of the bearing has a first resistance moment in the direction of its bending plane and a second resistance moment in the direction perpendicular to its bending plane, Is at least twice the magnitude of the first resistance moment. In order to obtain the rigidity of the flexure of the bearing, the flexure has a bending axis extending perpendicular to its bending plane, and the length of the bending direction of the flexure of the bearing is perpendicular to the bending axis of the bearing. At least twice the maximum cross sectional dimension of the flexure of the bearing extending in the bending direction is sufficient. In the optical module 108 according to the embodiments described here, the bending axis 11 of the bearing
3.1 may be parallel to the bipod plane where the bipod can be adjusted with the lever 113.1 held by the bearing.

In order to further reduce the described range of inclination, each lever 113 in this example is connected to the outer ring via a flexure device 117 acting as a support joint. The flexure device 117 is configured as a substantially U-shaped support arm (in the xy plane) having three additional second flexures 117.1, each of which has a bending axis of
It extends parallel to the bending axis of the second flexure 113.1. This means that the flexure device 117 can serve as a support for the inclination of the lever 113 as described above, at the same time as following the rotational movement of the lever 113.

The support arm 117 has a second flexure 113.1 with respect to the first connection region 114.5.
As a result of which a particularly good support for the inclination of the lever can be obtained. However, it will be appreciated that the support for the tilt of the lever may be located at any other suitable point.

If it is necessary to obtain a particularly good support for the inclination, the dashed outline 11 in FIG.
8, the portion of the outer ring 110 on which the support arm 117 is disposed (effectively protruding) is the lever 1 of the outer ring 110 via a reinforcing (for example, screwed) support plate.
It can also be made to join to the part located in the other side of 13. FIG.

Obviously, in other variants of the invention, the additional support for the inclination of the lever can also be configured in other ways. However, if necessary, this can be omitted entirely if the second flexure ensures sufficient support with the expected static and dynamic loads.

In order to reduce the tilt of the lever 113 described above in the embodiment described for the optical module 108, the lever may have at least one further flexure connected to the support unit 110. At this time, the further flexure of the lever is the flexure 11 of the bearing.
It is advantageous to have exactly one bending plane parallel to the 3.1 bending plane. Furthermore, the further flexure of the lever preferably also has a rigid structure perpendicular to its bending plane. It is also advantageous if the further flexure is arranged at a distance from the bearing less than twice the length of the lever load arm. As a result, the deflection ratio of the fulcrum / force point distance to the fulcrum / force point (force to load arm) is usually large, often greater than 5, in an additional flexure with an additional flexure supporting the lever. Only relatively small motion compensation is required, and for this reason, this further flexure can have a rigid structure as well. Generally, the lever is a single-sided or first-sided lever.
double-sided lever). Alternatively or additionally, to reduce the slope,
In particular, the bipod brace 914 is further connected to the support unit 11 via the flexure 913.2.
When supported by 0, the lever can be joined to the bipod brace 914 via flexure 914.1 (see FIG. 16).

In particular, as can be inferred from FIG. 7, the lever 113 is connected to the adjusting device 116 at its free end not facing the support body 113, and the rotation around the rotation axis of the lever 113 is set via the adjusting device 116. Can be done. In the example shown, this is a generally known passive device that can make coarse and fine adjustments of the rotation of the lever by various means (screw connection and adjustment washers). It is obvious here that in addition to or instead of this passive adjustment device as mentioned, an active adjustment device (operating according to any operating principle or combination of operating principles) may be provided.

However, this configuration is particularly advantageous (for example, from the first mentioned patent document 2).
A difference from the known configuration is that a pretensioning device 119 for the lever 113 is incorporated in the swinging surface of the lever 113. The pretensioning device 119 is here configured as a simple leaf spring that is incorporated into the gap between the outer ring 110 and the lever 113. This has the advantage that no additional tilting moment is applied to the lever 113 due to the pretensioning force. Further, the leaf spring 119 itself (because of its high rigidity), the lever 11
It can still serve as an inclined support of 3 or support the lever 113.

In a further embodiment of the optical module 108 described herein, the lever may comprise a pretensioning device and an adjusting device as described above, for example.

As can be inferred from FIG. 5 in particular, in this example, the first flexures 114.1 and 114.
3 are configured to be short and therefore pure rotary joints transverse to their bending axes, while the two first flexures 114.2 and 114.4 are also Configured as an elongated leaf spring element transverse to the axis. This configuration means that the two first flexures 114.2 and 114.4 can also absorb torsion about an axis transverse to their bending axis (here the x-axis).

In this way, for example, its inclination about an axis extending transverse to the optical axis of the optical element 106.1 can be compensated by the support element 111. Thus, in this example, the support member 114 provides a limited motion of the optical element 106.1 relative to the outer ring with exactly one degree of freedom (ie, translation in the x direction).

However, it is self-evident that in certain variants of the invention (for example in the case of pure translational adjustment of the optical element) there is no possibility of such tilt compensation. In such a case,
For example, all four first flexures can be implemented as pure rotary joints (transverse to the short bending axis). In this case, the movement limitation of the optical element 106.1 with respect to the outer ring is performed with two degrees of freedom (that is, translation in the x direction and rotation around the x direction).

FIG. 8 shows a flow diagram of a preferred variant of the method according to the invention for supporting the optical element 106.1 performed in the microlithography apparatus 101. FIG.

Initially, in step 120.1, the components of optical module 108 are available as described above.

Subsequently, in step 120.2, the optical element 106.1 and the holding device 109 are connected to each other.

Subsequently, in step 120.3, the position and orientation of the optical element are set by the above-described method via the adjusting device 116.

Second Embodiment In the following, a further preferred embodiment of the support element 211 according to the invention will be described with reference to FIGS. 1, 2 and 9A. The support element 211 can be used in place of the support element 111 in the imaging apparatus 101. The basic structure of the support element 211 and its method of operation are shown in FIG.
In order to correspond to the support element 111 from the above, only the differences are dealt with here. In particular, similar components are given reference numerals with a value of 100 added. Unless otherwise stated below, reference is particularly made to the above description for the features of the components.

FIG. 9A shows a cross section of the region of the support member 214. The only difference between the support element 211 and the support element 111 is that the first flexures 214.2 and 214.4 of the support element 214 are configured as leaf spring elements extending transverse to the x direction. . In this way as well, since a movement restriction with exactly one degree of freedom (ie rotation about the x axis) occurs, static support of the optical element 106.1 is again obtained here.

9B-9D show a further variation of the arrangement and configuration of the first flexures 214.1-214.4. Here, it is obvious that the configuration and arrangement of the flexures 214.1 to 241.4 can basically be arbitrarily selected. Thus, for example, FIG. 9B shows flexure 2
14.1 to 214.4 show a modification of the arrangement of the first embodiment in which the order is changed in the direction of force flow.

The placement of the flexures here will generally depend on the desired movements or conditions that are not related to stiffness, such as fabrication and / or assembly capabilities. In particular, the motion transmission ratio between the displacement of the first connection region 214.5 and the displacement of the second connection region 241.6 depends on the distance between the two first flexures 214.2 and 214.4. Determined.

FIG. 9C shows the variant already described above in connection with the first embodiment, in which all flexures are implemented as short joints transverse to the bending axis, and thus as rotary joints.

In the variant from FIG. 9D, the two leaf spring flexures 214.2 and 214.4 are aligned in the direction K of force flow. Consequently, as a result, their bending axes are arranged to be coplanar with the direction K of force flow. The same applies to the configuration from FIG. 9C in other respects. Thus, the desired distribution or setting of the type of stress that occurs under load (eg, reduction of bending stress, generation of pure tensile / compressive stress) is finally obtained.

In the optical module 108 according to the embodiments described herein, the bipod brace is
They can be arranged in the longitudinal direction parallel to the surface of the support unit, and the brad foot and the brace head of the bipod brace each have at least one flexure so that their connecting line makes an angle with the surface of the support unit. 214.2 and 214.4 are joined together in the diametrical direction.

Third Embodiment In the following, with reference to FIGS. 1, 2 and 10A, a further preferred embodiment of the support element 311 according to the invention will be described. The support element 311 can be used in place of the support element 111 in the imaging apparatus 101. Since the basic structure of the support element 311 and its method of operation correspond to the support element 111 from FIG. 2, only the differences will be dealt with here. In particular, similar components are given reference numerals with a value of 200 added. Unless otherwise stated below, reference is particularly made to the above description for the features of the components.

FIG. 10A shows a cross section of the region of the support member 314. The only difference between the support element 311 and the support element 111 is that the first flexure 314.1 of the support element 314 (extends in the x direction).
It is configured as a leaf spring element and a flexure similar to the flexure 114.3 is omitted. In other words, here the flexure 314.1 first has two bending elements 114.
The functions of 1 and 114.3 are integrated, and the twisting thereof also allows separation of the tilting motion of the optical element 106.1 (centered around a tilting axis extending transverse to the optical axis). In this way as well, a statically defined support of the optical element 106.1 is obtained here, since an operation restriction with exactly one degree of freedom (ie rotation about the x axis) occurs.

FIG. 10B shows a configuration similar in configuration and configuration and function from FIG. 10A in which two short leaf springs 314.1 and 314.3 are arranged directly adjacent to each other instead of the long leaf springs.

Fourth Embodiment In the following, further preferred embodiments of the support element 411 according to the invention will be described with reference to FIGS. 1, 2, 11A and 11B. The support element 411 can be used in place of the support element 111 in the imaging apparatus 101. Since the basic structure of the support element 311 and its method of operation correspond to the support element 111 from FIG. 2, only the differences will be dealt with here. In particular,
Similar components are labeled with a value of 300. Unless otherwise stated below, reference is particularly made to the above description for the features of the components.

In this configuration, the support member 414 has two first flexures 414.1 and 414.3.
(They have their bending axes extending parallel to the y direction), so that in the region of the support member 414, a four degree of freedom motion limitation occurs. Furthermore, the separation of the two degrees of freedom occurs in the region of the second connecting element 415 in this variant. For this purpose, again, two second flexures 415.1 and 415.2 of a second connecting element 415 elongated along their bending axes are provided. The flexure 415.1 separates the tilting action of the optical element 106.1 about the tilt axis extending in a direction transverse to the optical axis, whereas the flexure 415.2 is centered on the optical axis of the optical element. This causes separation of rotational motion.

In this configuration, the tilting operation and the rotation operation of the optical element 106.1 are separated from each other.
Occurs in the immediate vicinity of 1, so that even if the position of the optical element deviates from its set value, the deviation is farther away from the optical element 106.1 in the direction of the force flow than when the separating element is arranged. Has the advantage of being small.

The embodiment of the optical module 108 described here is similar to the fourth embodiment in that at least one connecting the braid head of the bipod brace directly or indirectly to the optical element.
Comprising one joint unit, the joint unit comprising at least one flexure 414.3 whose bending plane is parallel to the bipod plane of the corresponding bipod. further,
In the optical module 108, alternatively or additionally, the joint unit connecting the optical elements is at least one whose bending plane is perpendicular to the bipod plane of the corresponding bipod.
It may contain two flexures.

In a further embodiment of the optical module 108 described herein, the bipod brace head is connected to the connecting element 415 via a joint unit connecting the optical elements, respectively.
It can be connected to the holding element 112 holding the optical element via the. Here, the holding element 112 or the connecting element 415 may comprise at least one further flexure 415.1, 415.2. In this case, the further flexures 415.1, 415.2 are perpendicular to the bipod plane in the direction of the optical axis of the optical element and / or perpendicular to the bipod plane perpendicular to the optical axis of the optical element. It can have a bending plane.

Fifth and Sixth Embodiment In the following, referring to FIGS. 1, 2, 12, and 13, the support element 5 according to the invention
Further preferred embodiments of 11 and 611 are described. The support element 611 511 may be used in place of the support element 411 in the imaging device 101. Support elements 511 and 611
The basic structure and its method of operation correspond to the support element 411 from FIG. 11A, so only the differences will be dealt with here. In particular, similar components are provided with a reference number added with a value of 100 or 200. Unless otherwise stated below, reference is particularly made to the above description for the features of the components.

The difference between the support element 511 and the support element 411 is that the second flexure 515.
Provides a separation of three degrees of freedom via 1, ie the separation of the tilting and rotation of the optical element 106.1 as well as the radial movement of the optical element 106.1 (and hence its radial movement) It is to be done.

Thus, in this configuration, the support member 514 and the second connecting element 515 provide a limited operation of the optical element 106.1 relative to the outer ring 110 with exactly one degree of freedom (ie, translation in the x direction).

Similar operational limitations are obtained with the support element 611 from FIG.
The leaf spring 615.1 is more rigid with respect to the separation of the rotational movement of its one around its optical axis.

Seventh Embodiment In the following, further preferred embodiments of the support element 711 according to the invention will be described with reference to FIGS. 1, 2 and 14A. The support element 711 can be used in place of the support element in the imaging device 101. The basic structure of the support element 711 and how it operates is shown in FIG.
In order to correspond to the support element 411, only the differences will be dealt with here. In particular, similar components are given reference numerals with a value of 300 added. Unless otherwise stated below, reference is particularly made to the above description for the features of the components.

The difference between the support element 711 and the support element 411 is that a three-degree-of-freedom separation is provided via the L-shaped leaf spring-like second flexure 715.1, ie the tilting movement of the optical element 106.1. In addition to the separation of the rotational movement, the separation of the radial movement of the optical element 106.1 (and hence its radial movement) also occurs.

FIGS. 14B-14D show further variations of this flexure 715.2 configuration, where the curved path of the flexure 715.2 in a cut plane perpendicular to the bending axis, respectively, It is a decisive feature that ensures multiple separations.

FIG. 14E illustrates the parasitic motion problem that can occur in the optical element in the x direction.
A further variant is shown which can be solved by 5.3.

An eighth embodiment,
In the following, with reference to FIGS. 1, 2 and 15A, further preferred embodiments of the support element 811 according to the invention will be described. The support element 811 is a support element 1 in the imaging apparatus 101.
11 can be used instead. Since the basic structure of the support element 811 and its method of operation correspond to the support element 111 from FIG. 2, only the differences will be dealt with here. In particular, like components are labeled with a value of 700 added. Unless otherwise stated below, reference is particularly made to the above description for the features of the components.

The only difference from the support element 111 is here the configuration of the second flexure 813.1 connecting the lever 813 to the outer ring 110. In this example, in order to improve the tilt support of the lever 813, the flexure 813.1 is formed by two leaf spring-like elements, and their axes intersect to define the instantaneous rotation center of the rotation operation of the lever 813.

Figures 15B to 15D show a further variant of this configuration, in which the arrangement of the two leaf spring-like elements constituting the flexure 813.1 is different.

In a further embodiment of the optical module 108 described here, the bearing flexure 8
13.1 may include a plurality of flexures each having a parallel bending plane that constitutes the center of rotation. Here, it is preferable that the bending elements constituting the center of rotation are configured so as to be rigid in a direction perpendicular to their respective bending planes.

Ninth Embodiment In the following, with reference to FIGS. 1, 2 and 16, a further preferred embodiment of the support element 911 according to the invention will be described. The support element 911 is a support element 11 in the imaging apparatus 101.
Can be used instead of 1. Since the basic structure of the support element 911 and its method of operation correspond to the support element 111 from FIG. 2, only the differences will be dealt with here. In particular, similar components are labeled with a reference value of 800. Unless otherwise stated below, reference is particularly made to the above description for the features of the components.

The difference from the support element 111 lies here in the configuration of the additional tilt support of the lever 913. In this example, the lever 913 is not directly supported, but an additional leaf spring-shaped flexure 913.2 is provided, through which the lever 91 (centered on the x-axis) is provided.
Support member 914 is also supported (in the direction of the z-axis) to avoid a tilt of 3 and the resulting tilt of support member 114.

A further difference is that the first flexure 914.1 has a leaf spring configuration as well. Since the axes of the leaf spring-shaped flexures 914.1 and 913 intersect, the instantaneous rotation center of the compensating operation between the lever 913 and the support member 914 regarding the rotating operation of the lever 913 is defined in this way.

Tenth Embodiment In the following, with reference to FIGS. 1, 2 and 17A, a further preferred embodiment of the support element 1011 according to the invention will be described. The support element 1011 can be used in place of the support element 111 in the imaging apparatus 101. The basic structure of the support element 1011 and its method of operation are:
In order to correspond to the support element 111 from FIG. 2, only the differences are dealt with here. In particular, similar components are labeled with a value of 900 added. Unless otherwise stated below, reference is particularly made to the above description for the features of the components.

The only difference from the support element 111 is the configuration of the pretensioning device 1019 that causes the lever 1013 to collide with the pretension. In this example, the leaf spring 1019 is disposed in the region of the flexure 1013.1 that joins the lever to the outer ring 1100.

FIG. 17B shows a further variation of this configuration where the pretensioner 1019 is integrated directly into the flexure 1013.1. For this purpose, a leaf spring-like element having a U-shaped cross section (in the xy plane) is integrally joined to the lever 1013. The pretension can be set by an adjusting screw 1019.1 (or similar adjusting means) joined to the outer ring 110.

The invention has been described in detail with examples from the field of microlithography exclusively with light of a wavelength of 193 nm. However, it is obvious that the invention can be used equally well in any other application or imaging method, especially at any wavelength of light used for imaging.

Claims (49)

An optical module,
A support unit;
At least one bipod that holds and / or positions the optical elements of a microlithographic projection exposure system relative to the support unit;
With
The bipod includes two bipod braces, each of which is directly or indirectly connected to the support unit at a first end forming a brace foot;
Each of the bipod braces is directly or indirectly connected to the optical element at a second end forming a brace head, and at least one brace head and a connection line connecting two brace feet are on the bipod plane. It is supposed to be located in
The spacing between the brace feet is at least one lever connected to the support unit via a bearing and movable in at least one movement direction by engaging at least one brace foot via a joint unit. Can be adjusted,
The at least one direction of movement of the lever is out of the bipod plane;
The lever is further connected to the support unit via a support joint, the support joint being connected to the lever in the region of the joint unit.   The optical module according to claim 1, wherein the support joint is disposed on the opposite side of the bearing with respect to the joint unit.   The optical module according to claim 1, wherein the support joint is configured as a flexure device.   The optical module according to claim 1, wherein the support joint is configured as a substantially U-shaped support arm having three support joint flexures.   The bearing has a bearing flexure that defines a bending axis of the bearing flexure, and the three support joint flexures define a bending axis of the support joint flexure that extends substantially parallel to the bending axis of the bearing flexure. Item 5. The optical module according to Item 4. The bearing defines a moving surface of the lever;
6. The optical device according to claim 1, wherein the support joint is configured to substantially prevent the lever from tilting about a tilt axis in a motion plane of the lever. 7. module. The bearing is connected to a first support unit portion of the support unit; the support joint is connected to a second support unit portion of the support unit;
The optical module according to claim 1, wherein the lever is disposed between the first support unit portion and the second support unit portion.   The optical module according to claim 7, wherein the support joint is disposed at a free end of the second support unit portion.   The optical module according to claim 7, wherein the support unit includes a substantially ring-shaped element forming the first support unit portion and the second support unit portion.   The optical module according to claim 7, wherein the second support unit portion is supported by the first support unit portion via a reinforcing element.   11. The joint unit has at least one joint unit flexure having exactly one bending plane, the joint unit flexure having a rigid configuration perpendicular to the bending plane. The optical module according to any one of the above.   The optical module according to claim 1, wherein a distance between the brace feet along the connection line is larger than a distance between the brace heads.   The optical module according to claim 1, wherein a distance between the brace feet along the connection line is smaller than a distance between the brace heads.   The joint unit flexure has a first resistance moment in the direction of the bending plane, and a second resistance moment in a direction perpendicular to the bending plane, the second resistance moment being The optical module according to claim 1, wherein the optical module is at least twice the magnitude of the first resistance moment.   The joint unit flexure has a bending axis extending perpendicular to the bending plane, and the length of the joint unit flexure in the direction of the bending axis is perpendicular to the bending axis. The optical module according to claim 1, wherein the optical module is at least twice the maximum cross-sectional dimension of the at least one joint unit flexure that extends.   16. The operation direction of the lever is perpendicular to the bipod plane, and the bending plane of the at least one joint unit flexure is perpendicular to the bipod plane. The optical module according to Item 1.   The optical module according to claim 15 or 16, wherein the operating direction of the lever is perpendicular to the bipod plane, and the bending axis of the at least one joint unit flexure is parallel to the bipod plane. .   18. The optical module according to any one of the preceding claims, wherein the joint unit comprises a further joint unit flexure having a further bending plane.   19. The optical module of claim 18, wherein the further bending plane of the further joint unit flexure is perpendicular to the bending plane of the at least one joint unit flexure.   20. An optical module according to any one of claims 18 or 19, wherein the further joint unit flexure has a rigid configuration perpendicular to the bending plane.   21. The optical module according to claim 20, wherein the further joint unit flexure has a further bending axis perpendicular to the further bending plane.   22. The further joint unit flexure has a resistance pole moment that is at least twice a resistance moment in the direction of the further bending plane relative to a torsion axis perpendicular to the further bending axis. Optical module.   The further joint unit flexure has a first resistance moment in the direction of the further bending plane and a second resistance moment perpendicular to the further bending plane, the second resistance moment 23. The optical module according to any one of claims 20 to 22, wherein is at least twice the magnitude of the first resistance moment.   24. The further bending plane of the further joint unit flexure is either perpendicular to the plane of symmetry of the optical element or parallel to the optical axis in the projection exposure system. The optical module according to item.   25. The optical module according to any one of claims 18 to 24, wherein the further bending plane of the further joint unit flexure is parallel to the bipod plane.   The bending plane of the at least one joint unit flexure of the joint unit is parallel to a plane of symmetry of the optical element or parallel to a plane perpendicular to the optical axis in the projection exposure system; The optical module according to claim 1.   The bipod braces are arranged parallel to the surface of the support unit in their longitudinal direction, and the brace foot and the brace head of the bipod brace connect the flexure of the brace foot and the flexure of the brace head, respectively. 27. The optical module according to any one of claims 1 to 26, comprising at least one flexure such that a connecting line intersects the surface of the support unit at an angle.   28. The optical module according to claim 1, wherein the at least one joint unit flexure of the joint unit or the further joint unit flexure is configured as a leaf spring.   The optical module according to any one of claims 1 to 28, wherein the bearing of the lever assigned to each of the bipods is configured as a bearing flexure that connects the lever to the support unit.   30. The optical module of claim 29, wherein the bearing flexure has exactly one bending plane, and the bearing flexure has a rigid structure perpendicular to the bending plane.   The bearing flexure has a first resistance moment in the direction of the bending plane and a second resistance moment in a direction perpendicular to the bending plane, the second resistance moment being the first resistance moment. The optical module according to claim 30, wherein the optical module is at least twice the magnitude of the resistance moment.   The bearing flexure has a bending axis extending perpendicular to the bending plane, and the length of the bearing flexure in the direction of the bending axis extends in a bending direction perpendicular to the bending axis of the bearing. 32. The optical module according to claim 30 or 31, wherein the optical module is at least twice the maximum cross-sectional dimension of the bearing flexure.   The optical module according to claim 32, wherein the bending axis of the bearing is parallel to the bipod plane, and one bipod brace of the bipod is adjustable with the lever held by the bearing.   34. The bending plane of the bearing is parallel to a plane of symmetry of the optical element or parallel to a plane perpendicular to the optical axis in the projection exposure system. An optical module according to 1.   The optical module according to any one of claims 29 to 34, wherein the bearing includes a plurality of bearing flexures, and the plurality of bearing flexures define parallel bending planes and constitute a rotation center.   36. The optical module of claim 35, wherein the bearing flexures that constitute the center of rotation are configured to be substantially rigid in a direction perpendicular to their respective bending planes.   37. The optical module according to any one of claims 1 to 36, wherein the lever is configured as a second type or a first type.   A brace foot of at least one bipod brace of the bipod is connected to the support unit via a bearing flexure, and the bending plane of the bearing flexure is at least one joint unit of the joint unit that engages the brace foot. The optical module according to claim 1, wherein the optical module is parallel to the bending plane of the flexure.   39. The optical module of claim 38, wherein the joint unit flexure that connects the brace foot with the support unit is configured to be rigid in a direction perpendicular to its bending plane.   40. The optical module according to any one of claims 30 to 39, wherein the lever is connected to the support unit via at least one further flexure.   The further flexure of the lever has exactly one bending plane parallel to the bending plane of the bearing flexure, and the further flexure of the lever is substantially rigid in a direction perpendicular to the bending plane. 41. The optical module of claim 40, configured as follows.   42. The optical module according to claim 40 or 41, wherein the further flexure is disposed at a distance from the bearing that is less than twice the length of the distance between the fulcrum and the action point of the lever.   At least one brace head of a bipod brace connected directly or indirectly to the optical element comprises a further joint unit comprising at least one joint unit flexure, the at least one flexure bending plane correspondingly 43. The optical module according to any one of claims 1-42, wherein the optical module is parallel to the bipod plane of the bipod.   44. The optical module of claim 43, wherein the further joint unit connected to the optical element comprises at least one further joint unit flexure, wherein the bending plane is perpendicular to the bipod plane of the corresponding bipod. .   45. The brace head of the bipod connected to the optical element is connected to a holding element that holds the optical element via a connecting element via the further joint unit, respectively. The optical module as described.   46. The optical module according to claim 45, wherein the holding element and / or the connecting element comprises at least one further flexure.   The flexure has a bending plane perpendicular to the bipod plane in the direction of the optical axis of the optical element and / or perpendicular to the bipod plane in a direction perpendicular to the optical axis of the optical element. The optical module according to claim 46, comprising:   The optical module according to claim 1, wherein the lever includes a pretension device and an adjustment device. In addition to the at least one bipod, two further bipods are provided to form a hexapod structure for holding and / or positioning the optical element relative to the support unit;
The two additional bipods are configured substantially identical to the at least one bipod;
49. The optical module according to any one of the preceding claims, wherein each of the two further bipods is assigned a further lever corresponding to the lever and a further joint unit corresponding to the joint unit.